“Birds are everywhere; people who study them can’t be,” says Pat Leonard of the Cornell Lab of Ornithology. “The question is very simple and very basic — what birds are there? A lot of people get hooked on it; they’ll say, ‘I never knew this was in my backyard.’”

As an annual four-day event in its 16th season, the GBBC allows all levels of birdwatchers to delve into citizen science by simply counting birds in their own backyard. According to the GBBC website, “participants tally the number of individual birds of each species they see during their count period.”

Afterward, they enter the numbers on the website. In recent years, GBBC officials received more than 100,000 bird checklists (each individual checklist a “pixel” of the entire big picture) from participants in the United States and Canada.

Leonard says they expect that number to grow because, beginning this year, the bird count goes global. “It will be interesting to see how many other countries get on board,” Leonard says. The world-wide count will allow scientists to understand how weather influences bird populations, how migration trends have changed, what diseases may have affected certain bird populations, and more. After the count, the GBBC will combine its data with other projects such as the Christmas Bird Count, Project FeederWatch and eBird to round out the picture of today’s birds.

Want more count results? The GBBC website allows users to view count results all the way back to 1998.